Wheelchairs are well known forms of transportation for increasing the mobility of the physically impaired. Wheelchairs are typically relatively small, single-person conveyances that generally comprise a seat supported by a frame which, in turn, is supported by two opposed drive wheels and two front casters. Other arrangements of casters are found on wheelchairs, including rear caster wheels and front and rear anti-tip wheels. One of the problems of caster wheels is that they sometimes oscillate rapidly when the wheelchair is moving, thereby causing annoyance to the wheelchair user. It would be advantageous if there could be developed an improved caster that moderates the oscillating or fluttering phenomenon.